Non-crystalline saliva-soluble coatings for elastomeric monofilament dental tapes

ABSTRACT

An improved dental tape treated with a substantive coating containing a crystal control substance, wherein said coating is: saliva soluble, substantially crystal-free, with a flaking value of less than about 20 and a release value of about 100.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from copending U.S. ProvisionalApplication Ser. No. 60/263,220, filed 22 Jan. 2001, the disclosure ofwhich is hereby incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to improved dental tapes. Specifically,the improved dental tapes of the present invention contain substantiallycrystal-free coatings that: (a) comprise from 20 to 120% by weight ofthe floss filament, (b) are saliva soluble and (c) exhibit a minimum offlaking. Yet these coatings are released in total into the oral cavityduring flossing and can contain ingredients such as abrasives that workwith the tape to help physically remove biofilms from interproximal andsubgingival surfaces, and chemotherapeutic ingredients affecting oralhealth and subsequent systemic diseases caused or exacerbated by poororal health. These coatings are particularly adapted to monofilamentdental tapes.

BACKGROUND OF THE INVENTION

Historically the purpose of dental floss was: (1) to dislodge and removedecomposing food material that accumulated at interproximal andsubgingival surfaces and could not be removed by brushing or rinsing,and (2) to dislodge and remove bacteria, plaque and/or calculus thataccumulated since the previous flossing and/or cleaning.

The concept of the use of dental floss for cleansing interproximalspaces appears to have been introduced by Parmly in 1819. Parmlysuggested the use of waxed silk to clean teeth of persons subject togingival inflammation.

The role of plaque, now described as subgingival biofilm, in gum diseaseis well documented. The need to physically remove subgingival biofilmsroutinely has become an accepted treatment for gum disease. Mechanicalremoval of subgingival biofilms can be achieved professionally through:scaling, planing, prophylaxis and polishing, and individually by toothbrushing, proxy brushing and flossing.

While these methods of physically removing subgingival biofilms fromtooth surfaces are effective and well accepted; gum disease continues tobe prevalent in the adult population, and consequently, improved meansfor the individual to physically remove subgingival biofilms routinelyare indicated.

Furthermore, the spacing between teeth is not uniform and it variesconsiderably, not only from one place to another between the same pairof teeth, but also from one pair of teeth to another pair of teeth. Thespacing varies in the same individual, among different individuals, andespecially in the case of twisted teeth and teeth that have fillings,crowns, etc.

To accommodate tight spacing and those interproximal contacts that donot allow multifilament dental floss to be worked between teeth withoutfraying, breaking, etc., a vast array of “TEFLON” dental flosses havebeen commercialized. These shred-resistant, monofilament tapes aredescribed in detail in the following U.S. Patents, which are herebyincorporated by reference: U.S. Pat. Nos. 3,664,915; 3,953,566;3,962,153; 4,096,227; 4,187,390; 4,256,806; 4,385,093; 4,478,665;4,776,358; 5,033,488; 5,209,251; 5,220,932; 5,518,012; 5,718,251;5,765,576; and 5,911,228.

The TEFLON-type tapes available commercially in the marketplace today,include: Gore's Glide®, Oral-B's Satin Floss®, Johnson & Johnson's EasySlide®, and Colgate's Totals). All of these tapes can be worked betweentight spaces with a minimum of fraying and breaking. Yet, unlike theirmultifilament counterparts such as Johnson & Johnson's woven floss,REACH® Gentle Gum Care, during flossing, these tapes do not releasesubstantial quantities of cleaners, abrasives, tartar controlingredients, whiteners and active ingredients such as fluoride,antimicrobials, antibiotics, etc. The net of this shortcoming in failingto deliver substantial quantities of ingredients to those sites beingflossed is that the tapes are generally perceived as most convenient infitting between teeth, but unfortunately, they are generally perceivedas: “not cleaning”, “not working”, “not doing much”, etc., once they arepositioned between teeth.

When substantial quantities of cleaning, conditioning and treatingsubstances are coated onto tapes, the resultant tapes are characterizedby excessive flaking and breaking off of these coatings duringprocessing, dispensing and wrapping of tape around the fingers. As aresult, there are no commercial tapes available with substantialcoatings of releasable ingredients suitable for working into andphysically removing biofilms from interproximal and subgingival spaces.

Biofilms are notorious throughout nature for being difficult to remove.Working a monofilament tape over biofilms in the absence of substantialquantities of cleaners, abrasives, etc., is not effective in physicallyremoving and/or disrupting substantial quantities of biofilms. The netis, critical biofilm buildup interproximally and subgingivally cannot beeffectively physically removed with routine flossing with currentcommercial dental tapes, both PTFE tapes and bicomponent tapes.

Monofilament interproximal devices are described and claimed in: U.S.Pat. Nos. Re 35,439; 3,800,812; 4,974,615; 5,760,117; 5,433,226;5,479,952; 5,503,842; 5,755,243; 5,845,652; 5,884,639; 5,918,609;5,962,572; 5,998,431; 6,003,525; 6,083,208; 6,148,830; 6,161,555; and6,027,592, the disclosures of which are hereby incorporated herein byreference. These dental tapes generally have serious shortcomings ingentleness, in delivering coatings during flossing and in being handledeasily and conveniently during flossing Polytetrafluoroethylene (PTFE)based interproximal devices are described in: U.S. Pat. Nos. 5,209,251;5,033,488; 5,518,012; 5,911,228; 5,220,932; 4,776,358; 5,718,251;5,848,600; 5,787,758; and 5,765,576. To date, no commercial versions ofthese tapes have been coated effectively and cannot be used to deliveractive ingredients, interproximally and subgingivally during flossing.Handling during flossing is difficult. Most have to provide a consumeracceptable edge. Many are plagued with serious dimensional inconsistencyproblems, as well.

Several Patent Applications have been filed on monofilament dental tapeswith coatings comprising from between about 20% by weight and about 120%by weight of the monofilament tape. These are described in copendingU.S. Provisional Patent Application Ser. Nos. 60/227,433 and 60/227,255,filed 23 Aug. 2000 and Ser. No. 60/263,220, filed 22 Jan. 2001, all ofwhich are hereby incorporated by reference.

There is clearly a need for a commercial, shred-resistant tape that iscoated with releasable ingredients that help disrupt and/or physicallyremove biofilms from critical interproximal and subgingival sites whenused regularly, and deliver chemotherapeutic agents as required in asite-specific manner.

SUMMARY OF THE INVENTION

The present invention centers around the observation that thesubstantivity of coatings onto flexible surfaces, including dentaltapes, can be enhanced such that during flexure of the surface, theseenhanced coatings remain substantive to said surface and resistcracking, fracturing and flaking off. Specifically, it has been observedthat most coated flexible surfaces, especially those formulated to besaliva-soluble and carry effective quantities of abrasives, cleaners,surfactants, and chemotherapeutic agents, fracture along crystal facesduring flexure, thereafter releasing the ingredients from the flexiblesurface by cracking, chipping, flaking and/or falling off etc. Inresponse to these observations, it has been unexpectedly found that theaddition of certain substances to various coatings at relatively modestlevels reduces crystal formation while simultaneously enhancing thecoating's substantivity to flexible surfaces subjected to flexure, whichproperties thereby impart outstanding flake resistance and release valueto said tape.

Those coating additives that reduce, control and/or eliminate crystalformation and enhance the substantivity of the coating to flexiblesurfaces when added to these coatings at modest levels include certainaliphatic, long chain, fatty alcohols having from between about 10 and30 carbon atoms and/or various liquid surfactants such as polyethyleneglycol sorbitan dialiphatic esters.

Suitable aliphatic, long chain, fatty alcohols for the crystal-freecoatings of the present invention can be represented by the structuralformula ROH, wherein R represents a long chain alkyl group having from20 to 30 carbon atoms. Specific examples include: 1-decanol1-heptadecanol 1-pentacosanol 1-undecanol 1-octadecanol 1-hexacosanol1-dodecanol 1-nonadecanol 1-heptacosanol 1-tetradecanol 1-eicosanol1-octacosanol 1-pentadecanol 1-heneicosanol 1-nonacosanol 1-hexadecanol1-tricosanol 1-triacontasol 1-tetracosanol

Naturally occurring mixtures with substantial quantifies of these fattyalcohols, or isomers thereof; including those chemically derived fromnatural sources also constitute suitable sources of aliphatic, longchain fatty alcohols for the purpose of this invention.

The long chain fatty alcohols can be represented by the structuralformula ROH wherein R represents a long chain alkyl group having from 10to 30 carbon atoms. These can be purchased commercially from Stepan,Proctor & Gamble and Aldrich Chemical Co. and a variety of companiesprocessing vegetable and animal derived fatty alcohols.

Suitable liquid surfactants for the crystal-free coatings of the presentinvention include polyoxyethylene glycol sorbitan mono- and di-aliphaticesters represented by the general formula:

wherein R₁, R₂, R₃, R₄ are H or aliphatic acyl groups from (10 to 30)and the sum of w, x, y, and z is from between 20 and 80. These liquidsurfactants are available under the trade names Emsorb®, Span®, Tween®from Cognis N.A. and ICI. Specific examples of these include:

-   -   PEG 20 sorbitan monooleate (Tween® 80, ICI);    -   PEG 40 sorbitan monostearate (Span 60®, ICI); and    -   PEG 40 sorbitan diisostearate (Emsorb® 2726, Cognis, N.A.).

Similar esterified, PEG-based surfactants, which are known to thosehaving ordinary skilled in the art, are also suitable liquidsurfactants.

One preferred embodiment of this invention thus comprises substantivecoatings for flexible surfaces that, under flexure, resist cracking,flaking, breaking off, etc.

Another preferred embodiment of the present invention comprises ashred-resistant dental tape that physically removes biofilms frominterproximal and subgingival sites.

Another preferred embodiment of the invention comprises a method ofapplying substantive coatings of biofilm disrupting substances toshred-resistant tapes which coatings are released onto and worked intobiofilms during flossing.

A further preferred embodiment of the invention comprises shred-resistant tapes with substantive coatings that exhibit minimum flaking,yet achieve total release during flossing.

Yet another preferred embodiment of the invention comprises monofilamenttapes with substantially crystal-free coatings that are substantive,saliva soluble and exhibit with a minimum of flaking.

Still another preferred embodiment of the invention comprises ashred-resistant dental tape with a substantive coating that helpsphysically remove biofilms when released from the tape during flossing.

A further preferred embodiment of the present invention comprisessubstantive coatings for dental tapes that contain biofilm disruptingand physically removing ingredients along with biologically active orchemotherapeutic ingredients, all of which are largely or totallyreleased during flossing.

Still another preferred embodiment of the present invention comprises amethod for treating interproximal and subgingival sites to removesubgingival and interproximal biofilms while treating said sites withactive ingredients.

Yet another preferred embodiment of the invention comprises a method formanufacturing a shred-resistant dental tape that contains substantiallevels of biofilm disrupting/removing ingredients that do not flake off;yet are totally releasable during flossing.

Another preferred embodiment of the invention comprises coated dentaltapes with a flaking value of less than about 20.

A further preferred embodiment of the invention comprises a class ofcoated dental tapes with coating release values approaching about 100.

These and other embodiments of the invention are described in detailbelow.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

For the purposes of the present invention, “crystal-free” is defined asa smooth surface as distinguished from rough surface typical ofcrystalline coatings when observed through a 30× stereo zoom microscope.

For the purposes of the present invention, flaking resistance measuresthe propensity of the coatings of the present invention to flake off aflexible elastomeric, TEFLON®, bicomponent, or other polymeric dentaltapes during flexure. Flaking resistance (expressed as flake value) isbased on the reduction by weight of the crystal-free coating alterflexing, under suitably controlled and reproducible conditions, an18-inch piece of the coated tape for 30 seconds.

For the purposes of the present invention, release value is measuredafter 18-inches of the tape is thoroughly flossed for 60 seconds. Thepercent of the crystal-free coating removed from the tape duringflossing establishes the release value.

For the purposes of the present invention, dental tape is defined asmonofilament tapes including elastomeric tapes such as Perident'sFibaclean™, PTFE tapes, such as Gore's Glide®, J&J's Easy Slide® andColgate's Total® and bicomponent tapes such as Oral-B's Satin Tape®.

Certain petroleum waxes are suitable and preferred additional additivesfor the crystal-free coating of the present invention. These include anyof a range of relatively high molecular weight hydrocarbons(approximately C₁₆ to C₅₀), solid at room temperature, derived from thehigher-boiling petroleum fractions. There are three basic categories ofpetroleum wax: paraffin (crystalline), microcrystalline, and petroleum.Paraffin waxes are produced from the lighter lube oil distillates,generally by chilling the oil and filtering the crystallized wax theyhave a melting point range between 48° C. (118° F.) and 71° C. (160°F.), Fully refined paraffin waxes are dry, hard, and capable ofimparting good gloss. Microcrystalline waxes are produced from heavierlube distillates arid residue (one bottoms) usually by a combination ofsolvent dilution and chilling. They differ from paraffin waxes in havingpoorly defined crystalline structure, darer color, higher viscosity, andhigher melting points—ranging from 63° C. (148° F.) to 93° C. (200° F.).The microcrystalline grades also vary much more widely than paraffins intheir physical characteristics: some are ductile and others are brittleor crumble easily.

Petrolatum is derived from heavy residual lube stock by propane dilutionand filtering or centrifuging. It is microcrystalline in character andsemi-solid at room temperature. There are also heavier grades forindustrial applications, such as corrosion preventives, carbon paper,and butcher's wrap. Traditionally, the terms slack wax, scale wax andrefined wax were used to indicate limitations on oil content. Today,these classifications are less exact in their meanings, especially inthe distinction between slack wax and scale wax. Natural waxes such asbeeswax and carnauba wax are also suitable and may provide specificallydesired properties.

Suitable additional ingredients in the crystal-free coating of thepresent invention include anti-plaque ingredients˜such as MICRODENT® andULTRAMULSION™ as described in various U.S. Patents to Hill, et al.,including U.S. Pat. Nos. 4,911,927; 4,950,479; 5,032,387; 5,098,711;5,165,913; 5,538,667; 5.561,959; 5,66,374 and 5,733,529. The foregoingare incorporated herein by reference.

Various other active ingredients can be included in the substantivesaliva-soluble coatings applied to the various dental tapes of thepresent invention including antimicrobial, anti-tartar, whitening,cleaning, desensitizing, antibiotic, anti-inflammatory, anti-gingivitisingredients, as well as prostaglandin (PGE₂) and C-reactive proteincontrol substances.

Specific active ingredients suitable for use in the coated dental tapeof the present invention include: fluoride, potassium nitrate,triclosan, chlorhexidine, cetylpyridinium chlorhexidine, domaphenbromide, metronidazole, doxycycline, aspirin, the essential oils inListerine®, and mixtures thereof.

The substantial coatings for the dental tapes of the present inventioncan be further characterized as: (a) containing a crystal controlsubstance, (b) being saliva soluble, (c) substantially crystal-free, and(d) comprising from between about 20% and 120% by weight of said tape,and having a flake value of less than about 20 and a release value ofabout 100.

Elastomeric dental tapes such as described in the referenced co-pendingapplications coated with the crystal-free coatings of the presentinvention are described in Table 1 below. TABLE 1 EXAMPLE 1 2 3 4 5 6 78 9 10 11 12 13 14 15 16 17 18 Ingredient Ultramulsion 10-2.5 57.1 54.852.3 50.8 50.8 50.8 58.8 60.8 60.1 55.1 51.1 60.1 61.1 61.1 53.1 57.1POLOXAMER 407 60.1 60.1 Emsorb 2726 12.5 7.5 12.5 9 5 3 3 0 3 3 3 3 3 34 3 3 3 Stearyl Alcohol 9.2 10.5 8 7 11 13 15 16 15 15 15 15 15 15 10 815 15 Insoluble Saccharin 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.81.8 1.8 1.8 1.8 1.8 1.8 1.8 Propyl gallate 0.1 0.1 0.1 0.1 0.1 0.1 0.10.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Spicemint Flavor 4 4 4 4 4 44 4 5 5 5 5 5 5 5 5 5 5 Vanilla Mint Flavor 4 4 4 4 4 4 4 4 5 5 5 5 5 55 5 5 5 tetrasodium- 8 14 14 10 10 10 10 10 10 10 14 4 6 6 10 6pyrophosphate Dicalcium 10 6 10 phosphate Microcrystalline 10 10 10 0 00 0 5 5 0 7 10 7 7 Wax ML 445 Triclosan 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3Observation Need heat to wind y n y y n y Y y y y y y y y y y Bobbintack 1 5 5 3 4 4 3 2 4 4 3 3 4 3 4 4 (1 = poor, 5 = good) Flakeresistance Feels sticky (1 = no, 5 4 4 2 1 2 2 3 3 3 1 4 3 4 4 5 = very)Load of two 29/19 Na Na 43/50 28/11 53/39 58/43 33/20 51/40 33 46/5340/39 38/38 50/37 48 45 38/39 43/39 samples Release Value 98 97 100 96100 99 100 100 96 99 98 100 97 99 100 96 100 100

The present invention has been described in detail, including thepreferred embodiments thereof. However, it will be appreciated thatthose skilled in the art, upon consideration of the present disclosure,may make modifications and/or improvements on this invention and stillbe within the scope and spirit of this invention as set forth in thefollowing claims.

1-3. (canceled)
 4. A method for treating interproximal and subgingivalsites in the oral cavity with a coated monofilament dental tapecomprising flossing said sites with a coated monofilament dental tapehaving a substantive coating, wherein said coating: contains a crystalcontrol substance, is saliva soluble, is substantially crystal-free,comprises from between about 20% and about 120% by weight of said tape,and has a flake value of less than about 20 and a release value of about90 to
 100. 5. The method of claim 4, wherein said tape coating furthercomprises an active ingredient selected from the group consisting ofstannous fluoride, potassium nitrate, triclosan, chlorhexidine,cetylpyridinium chloride, domaphen bromide, metronidazole, doxycycline,aspirin, other non-steroidal anti-inflammatory drugs and mixturesthereof.
 6. A method for treating interproximal and subgingival sites inthe oral cavity for the purposes of mitigating, curing or otherwiseaffecting systemic diseases which are caused or exacerbated by poor oralhealth such as heart disease, diabetes, tobacco-use related disease,low-birth weight babies, immuno-compromised patients, said methodcomprising flossing said sites with a coated monofilament dental tapehaving a substantive coating, wherein said coating contains an activeingredient selected from the group consisting of stannous fluoride,potassium nitrate, triclosan, chlorhexidine, cetylpyridinium chloride,domaphen bromide, metronidazole, doxycycline, aspirin, othernon-steroidal anti-inflammatory drugs (NSAIDS) and mixtures thereof. 7.A method for physically removing subgingival biofilms from interproximaland subgingival sites in the oral cavity with a coated monofilamentdental tape comprising flossing said sites with a coated monofilamentdental tape having a substantive coating, wherein said coating: containsa crystal control substance is saliva soluble is substantiallycrystal-free comprises from between about 20% and about 120% by weightof said tape has a flake value of less than about 20 and a release valueof about 90 to
 100. 8-12. (canceled)
 13. The method for treatinginterproximal and subgingival sites in the oral cavity with the coatedmonofilament dental tape according to claim 5, wherein the activeingredient is delivered interproximally and subgingivally upon flossing.14. A substantive coating for monofilament dental tape comprising: atleast one crystal control substance; and an effective amount of at leastone biologically active ingredient, wherein the coating issaliva-soluble and comprises between about 20% and about 120% by weightof the tape and has a flake value of less than about 20 and a releasevalue of about 90 to 100, wherein the crystal control substance is asurfactant selected from the group consisting of TWEEN® 80 (POE sorbitanfatty acid ester), SPAN 60® (sorbitan monostearate), EMSORB® 2726(polyethyleneglycol (PEG)40 diisostearate), and POLOXAMER 407 (anonionic surfactant block copolymer of ethylene oxide and propyleneoxide).
 15. The substantive coating for monofilament dental tape ofclaim 14, wherein the anti-plaque substance is selected from the groupconsisting of emulsions of polydimethylsiloxanes and block copolymers ofethylene oxide and propylene oxide including MICRODENT® andULTRAMULSION®.
 16. Monofilament dental tape coated with a substantivecoating, the coating comprising: at least one crystal control substance;and an effective amount of at least one biologically active ingredient,wherein the coating is saliva-soluble and comprises between about 20%and about 120% by weight of the tape and has a flake value of less thanabout 20 and a release value of about 90 to 100, wherein themonofilament dental tape comprises an shred-resistant elastomer.
 17. Themonofilament dental tape of claim 16, wherein the elastomer comprisespolytetrafluoroethylene (TEFLON®).
 18. The monofilament dental tape ofclaim 16, wherein the elastomer comprises a bicomponent polymer.
 19. Themonofilament dental tape of claim 16, wherein the elastomer comprises ahomopolymer.
 20. The monofilament dental tape of claim 16, wherein theelastomer comprises a copolymer.